In the method for forming a self-assembly substance of probes in which a double-stranded self-assembly substance is formed by providing a plurality of pairs of probes each comprising n (n≧3) portions complementary to each other (may be referred to as a “HoneyComb probe: HCP” hereinafter) and hybridizing the probes so as to cross alternately (see U.S. Pat. No. 6,261,846, JP A 00-201687, and Japanese Patent Application No. 2000-98797, and this method may be referred to as a “PALSAR (Probe alternation link self-assembly reaction) method” hereinafter), a target gene is detected through formation of a double-stranded self-assembly substance by using only a pair of oligonucleotide probes and hybridizing the probes so as to cross-link alternately, but as only two oligonucleotide probes are used, there are several restrictions in regions of the oligonucleotide probes be used for detection of a target gene and regions for labeling with a fluorescent dye, an enzyme or an antibody.
Furthermore, as two oligonucleotide probes react to each other alternately, each region is in competition with each other, and a somewhat long reaction time is required for formation of a self-assembly substance.
In a pair of oligonucleotide probes used in the PALSAR method, only a pair of oligonucleotide probes are used and hybridized to each other so as to cross-link alternately, thereby forming a double-stranded self-assembly substance.
It is an object of the present invention to provide a novel method for forming a self-assembly substance of probes in which not only a pair of oligonucleotide probes, but each oligonucleotide probe is previously prepared as a plurality of dimer-probes, and the types are increased, thereby enabling a reaction time required for formation of a self-assembly substance to be further shortened and enabling regions of oligonucleotide probes which can be used for detection of a target gene and regions for labeling with a fluorescent dye, an enzyme or an antibody to be increased, and a method for detecting the self-assembly substance formed by the method for forming the self-assembly substance.
In the recent techniques for genetic diagnosis, various techniques represented by an enzyme immunoassay called EIA and a fluorescent labeling are used to detect a target gene, but in any method, use of an expensive enzyme, an antibody or fluorescent label and complicated operations are required.